The fabrication of electronic equipment, such as data processors, often involves assembly operations in both wrapped wire connections and cable and harness layouts. When such operations entail the use of twisted pairs of wires, it is necessary that each twisted pair be separated prior to electrical termination.
In order to make the task of untwisting wires less tedious and time consuming, a number of methods and devices have been developed to assist an operator. One such device for both untwisting a pair of wires and for stripping the portions of the separated wires is described in U.S. Pat. No. 3,736,606 to John F. Raum et al. In this patent, the tool body or handle includes a pair of fixed projections having respective rounded edges and defining a slot for receiving the twisted pair. As the wires are pulled between the projections, they are separated from each other. However, the untwisting and stripping functions of the tool are interdependent. A stripping blade mounted on a slideable member moves along with the wires relative to the tool body, from a first position, where the untwisting projections and the stripping blade are contiguous, to a second position controlled by a stop in the slide mechanism. Continued pulling of the wire after this second position has been reached, results in subtantially the entire length of the separated wires being stripped of insulation.
A later issued U.S. Pat. No. 3,875,601 to H. Kaufman, references the former patent and describes an "improved" tool for untwisting, cutting and stripping twisted wire pairs. A feature of the last mentioned tool is the use of untwister jaws comprised of a fixed jaw and a pivotable jaw which is operator actuated to apply pressure to the twisted wire as it is drawn between the jaws. The untwisting and stripping functions are substantially identical to those described hereinbefore in connection with the earlier patent.
The known tools are adapted to separate only one twisted pair at a time, which makes them inefficient when pluralities of twisted pairs are to be separated. Also, the degree of pressure applied to the twisted pair as they are separated may be detrimental. Thus, the pressure applied to the twisted pair insulation by the fixed projections of the Raum et al. tool will vary with the wire gauge and the spacing of the projections. On the other hand, the pressure applied to the twisted pair in the Kaufman tool is a function of the operator's actuation of the pivotable jaw in relation to the fixed jaw. In either case, excessive pressure may result in the stretching of the wire insulation, rendering the wire unusable.
What is desired is a twisted pair wire separator which is easy to operate and requires only slight pressure applied by an operator; which is capable of untwisting any desired length of wire; which can untwist one pair or a plurality of twisted pair simultaneously; which requires no adjustment for wires of different gauges; and which is maintenance free and wear-resistant. The wire separator of the present invention meets all of these requirements.